package com.itheima.map;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * @author Anomaly
 * @date 2023/1/20 19:42
 */
public class MapDemo {
    public static void main(String[] args) {
        Map<String, Integer> map = new HashMap<>();
        map.put("java", 3);
        map.put("python", 3);
        map.put("java", 3);

        System.out.println(map.remove("ad"));
        System.out.println(map.remove(null));

        map.put("go", null);
        map.put(null, null);

        System.out.println(map);

    }
}
